To use simple SVN password, go to /home/repository-authorization/edit/ and setup your SVN password. Then use the "Development url" starting with svn:// that should contains your username in lowercase. Enter your password when told to do so.

How can I specify externals? (a.k.a. embeds/libraries)

I tagged my project, but I don't see a file made!

Relax. The packager only runs on set intervals (approximately every 20 minutes), at which point it packages any new tags that were created since its last run. If you tag your project, give it up to 30 minutes or so (on the outside) to build the zip.

Changes to packager settings won't affect whether the packager detects a tag or not - only whether it actually packages it. If you change your packager settings before a tag is built, the new packager settings will be in effect when it goes to build the tag. There's no need to recommit a tag if you change your packaging settings, unless the tag was already built.